We"ve all seen it: a mother crouched on the floor, arms outstretched, cooing to her baby as he lopsidedly plops first one hand, then the other, on the carpet, dragging his chubby knees behind him. His short journey complete, he rolls onto his well-padded bottom and proudly explores the inside of his mouth with his fingers in an endearing show of gurgles and drool.

Children are oral and tactile, which can be a problem when they’re putting toys made of potentially harmful PVC plastic in their mouths. Jim Whitmer

Now look a little closer—not at the baby, but at the carpet. Clinging to the fibers could be any of the 75,000 synthetic chemicals developed and released into the environment since World War II. Fewer than half have been tested for potential toxicity to human beings, fewer still for children. And that child just put any number of them into his mouth.

This scenario doesn"t even include the particulates floating through the atmosphere, narrowing his small airways, or the peaches he was just fed, which contain residues of an organophosphate pesticide. Add in more details—his mother working in a dry cleaner during her pregnancy, his dad failing to kick that smoking habit—and a truly alarming picture can emerge.

Stacked Odds

Over time, the nature of childhood illness has evolved from epidemics like scarlet fever, smallpox and measles to chronic and disabling conditions like cancer, asthma, neurological impairment and hormone disorders. Though genetic predisposition certainly plays its part, Kenneth Olden, director of the National Institute of Environmental Health Sciences, likens the gene code"s influence over illness to merely loading the health risk gun. "The environment," he says, "pulls the trigger."

Environmental causes have been implicated in ailments from autism and attention deficit disorder to violent behavior, prompting widespread alarm among parents and activist groups and an unprecedented flood of research from the scientific community. "The more we learn about chemicals," says Dr. Gina Solomon, assistant clinical professor of medicine at the University of California-San Francisco, "the more we learn that very, very early in life is the most susceptible period."

Relative to their weight and size, children ingest more food, drink more water and breathe more air than adults. Their behavior only makes matters worse—children play on the ground, where there is more dust, paint chips and other dangers, and they frequently put their hands in their mouth. They also eat a much less varied diet, exposing them to concentrated pesticide residues. According to the U.S. Department of Agriculture (USDA), the average one-year-old drinks 21 times more apple juice, and eats two to seven times more grapes, bananas, pears, carrots and broccoli than an adult.

Children"s bodies are ill-equipped to handle such a firestorm of exposure. Childhood is a period of critical organ development and fast growth. The brain growth spurt lasts all the way through age two, and once disruption occurs in the nervous system, it cannot be repaired. A child"s natural defense mechanisms are not yet fully developed, especially during the first few months, and they are less able to break down certain toxins and excrete them. Molecules of many toxins, such as lead and other metals, are small enough to pass through the placenta to the fetus and can weaken or break down the protective screen of the blood-brain barrier.

This early exposure can cause subtle functional changes, says Solomon, "changes not in the appearance of the brain but in the way the brain works; changes not in the appearance of the internal organs but in the way those organs function."

Children are subject to social vulnerabilities as well, such as environmental injustice, poverty and malnutrition, which they are helpless to avoid or control. But we need not rely on this knowledge alone to spur parents, doctors, corporations and governments to action. The changing face of childhood illness is already clearly documented.

Asthma

Asthma affects almost five million American children under 18 years of age, and it is the number one cause of school absenteeism in America, outranking even colds and flu. Incidence increased more than 92 percent from 1982 to 1994, according to the American Lung Association. The Centers for Disease Control and Prevention (CDC) reports that asthma-induced deaths nearly doubled during this time.

Children"s airways have smaller diameters, so a small amount of pollutants may significantly narrow them, causing serious problems for a child that may be only a mild irritation to adults. Triggers vary widely, from cigarette smoke and molds and mildews to the off-gassing of vinyl materials. Children are particularly vulnerable to the effects of air pollutants, which in the short run can inflame the respiratory tract and lungs. In the long run, they can diminish lung function and the capacity to exercise, leading to increased rates of lung disease and cancer.

A greater metabolism means children need more oxygen relative to their size and body weight, causing them to breathe more rapidly and inhale more pollutants per pound. Their lungs continue to grow until the age of 20—development that can be thwarted by repeated exposure to pollutants.

Christiana Hepner, shown at age 6 in 1992, suffered hearing loss and learning disabilities after being exposed to lead paint chips in the family home.

Common air pollutants, such as emissions from cars, incinerators, chemical plants and refineries, and fine airborne particulates and smog, pose a special problem for urban children. In cities like New York and Los Angeles, asthma has become the leading cause of children"s hospital admissions. In 1990 alone, asthma was estimated to cost the nation $6 billion in health care expenditures.

Cancer

According to the American Cancer Society (ACS), cancer is the chief cause of death by disease in children under 15 years of age. In that group alone, an estimated 8,600 new cases and 1,500 deaths will occur in 2001. Thanks to better treatment, the death rate has dramatically declined (down 62 percent since 1960), but incidence has been climbing more than one percent a year for the past two decades.

Between 1973 and 1995, the National Cancer Institute (NCI) calculates that child brain and nervous system cancers increased 26 percent; acute lymphocytic leukemias grew 13.5 percent. These increases were even greater in children under five, where brain cancer rose 53 percent and leukemia 18 percent. In children so young, unhealthy lifestyles and diets are unlikely instigators; due to the rapidity of increase, so are genetic alterations.

Though improved detection may figure in, environmental causes may account for more than half of all cancers, says the ACS. Ionizing radiation and chemotherapy are the only proven causes of childhood leukemia, but other possible agents include radon, improper diet, solvents, tobacco smoke, alcohol, electromagnetic fields and infection. The Environmental P

rotection Agency (EPA) has identified 96 pesticides as potential human carcinogens, and one NCI study found that in children whose parents used store-bought home and garden pesticides, the rate of leukemia was four to seven times greater.

Endocrine Disruption

Hormones promote the normal development of many body functions, including those of the neurological, immune and reproductive systems. But some synthetic chemicals may mimic or block their function.

Pesticides, such as DDT, atrazine, chlordane and lindane, and industrial by-products like dioxin, furans and PCBs, have been identified as endocrine disruptors. These chemicals "biomagnify" in the food web and are "persistent," passing from generation to generation. A mother"s lifetime exposure is stored in her body, where it affects all prenatal and early postnatal development. A child"s exposure then continues through eating certain foods and breathing chemicals, and through behaviors such as crawling on contaminated surfaces and putting objects in her mouth.

Endocrine disruptors have been linked to testicular and ovarian cancer (which increased 78 and 65 percent, respectively, in U.S. teens between 1973 and 1995), a doubling in the male birth defect hypospadia (a deformed penis) and an increase in undescended and undersized testicles. A New Scientist study found that girls with the highest prenatal exposures to PCBs and dioxin entered puberty 11 months earlier than girls with lower exposures.

Birth Defects

Of the three million babies born in the U.S. each year, 250,000 (seven percent) are born with birth defects either immediately apparent or appearing later in life. This figure has increased between 1970 and 1985 for 18 of the 27 most common birth defects, some by as much as 1,700 percent.

If we take a cue from recent wildlife phenomena, some of these cases could be attributed to environmental pollution, which may genetically damage eggs or sperm or interfere with hormones that control sexual development in the brain. Florida alligators exposed to organochlorine pesticides grew penises one-third their normal size; fish and fish-eating birds in the Great Lakes, where PCBs are persistent, grew abnormal thyroids.

Today’s children are exposed to a huge number of toxic chemicals in their daily lives, including cleansers, pesticides and lawn treatments. Felicia Martinez / PhotoEdit.

A 1999 Journal of the American Medical Association study found that women occupationally exposed to organic solvents, such as factory workers, lab technicians and graphic designers, have a 13-fold increased chance of giving birth to a child with a major defect, including heart valve dysfunction, soft larynx cartilage, small penises and deafness. It was found that solvent-exposed women also suffered more miscarriages, and their babies had lower birth weights. Major components in lighter fluid, spot removers, aerosol sprays, paints, glues, cleaners and solvents—like so much else—can readily pass through the placenta to the fetus.

Impaired Mental Development

Educators and doctors have been slow to recognize that chemicals can also affect learning, says Theo Colburn, co-author of Our Stolen Future. "Some studies suggest that contaminants at levels currently found in the human population could impair mental development enough to cause a five-point loss in measurable IQ," she says. Even such a small drop in IQ could make a big difference in society—affecting a person"s ability to understand sophisticated problems.

Twelve million children under age 18 suffer from learning disabilities, reports the Learning Disabilities Association of America (LDA), and behavioral disorders such as hyperactivity and Attention Deficit Disorder—other possible signs of low-level chemical exposure—now affect one out of six U.S. children.

Some of the most insidious and well-documented chemical offenders include lead, mercury, PCBs and dioxin. Though these four are all federally regulated to some extent, 24 billion pounds of developmental and neurological toxins continue to be released in the U.S. each year, according to a recent report co-sponsored by the LDA. Only 1.2 billion pounds of these are reported to the EPA.

Baby Steps

As we continue to gain technical understanding of the routes of exposure, we gain practical understanding of steps that will reduce risk. Even before they are born, you can create for your children a healthy growing environment. Taking folic acid before pregnancy can prevent neural tube defects, such as spina bifida and anencephaly, which strike fetuses during the first few weeks. All women of childbearing age may also want to consider a simple blood test to ensure that their thyroid gland is functioning properly. "A baby"s intelligence depends as much on levels of thyroid hormone reaching the brain during critical periods of development as on inheriting smart genes," says Colburn. In one Pediatric Research study, decreased thyroid hormone in pre-term and low-birth-weight babies in the first weeks was associated with an increased need for special education by age nine.

Reducing the amount of fatty foods eaten prior to pregnancy is also a good bet, as that lessens exposure to persistent chemicals like PCBs and dioxin. Americans now carry dioxin levels in their bodies hundreds of times greater than the "acceptable" cancer risk defined by the EPA, and 95 percent of that results from eating red meat, fish and dairy products.

The African-American community of Diamond in Norco, Louisiana borders a giant Shell refinery. Chemical plants are one reason child asthma rates are soaring. Elaine Osowski.

Fish intake should be monitored in any case. The EPA now warns that 1.6 million women and children are at risk for mercury poisoning, as well as anyone consuming more than 30 pounds of fish per year. In fact, one out of every 10 U.S. women are at risk of having newborns with neurological problems due to mercury exposure in the womb, says a CDC study released earlier this year. Local freshwater advisories are helpful indicators. Pregnant women should avoid altogether certain carnivorous species such as swordfish, shark and tuna, which may hold exceptionally high levels of mercury contamination.

Feed a Cold

Dr. Howard Mielke, an environmental toxicologist with Xavier University, says "nutritional deficiencies certainly contribute enormously to the problem." A deficiency in calcium, for one, can promote accumulation of lead in the digestive tract, bones, brain and kidneys, which may result in lead poisoning. A study by the University of Medicine and Dentistry of New Jersey showed that nearly 60 percent of four- to eight-year-olds consume too little calcium. When exposed to lead in the environment, these children "may be faced with anemia, reduced IQ and learning difficulties as well as aggressive, violent and anti-social behavior," reports the study"s co-author, Dr. John Bogden.

Even nutritious foods may carry hazards. In 1998, the USDA found pesticide residues in 55 percent of nearly 7,000 fruits and vegetables tested; 29 percent had

residues of multiple pesticides. A 1999 Consumer Reports study analyzed government data on 27,000 samples of produce and computed toxicity scores for 27 foods. It found that one in 10 kids who eat Chilean grapes, four in 10 who eat U.S. peaches, and half of those who eat frozen U.S. winter squash will get more than the "safe" dose of a very toxic insecticide.

Edward Groth, director of Technical Policy and Public Service for the Consumers Union, is quick to point out that the report is "not about fearing food. It"s about giving people information so they can make smart choices." He says parents should not feed their children any fewer fruits and vegetables, but they should shop wisely. He adds that they should also buy foods known to have lower pesticide levels and, when possible, locally grown, organic produce (which a 1998 Consumer Reports study found had little or no residues). Preparation is important, as well. Adults should wash and peel many foods, like apples, peaches and pears, since some chemicals tend to concentrate near the skin. And parents should diversify children"s diets, spreading foods out over time, giving children"s immune systems time to catch up with ingestion.

Children eat two to seven more grapes, bananas, pears, carrots and broccoli than adults, according to the US Department of Agriculture.Isaac Hernandez

An even more effective approach may be to deliberately teach children about the links between their food and the environment, says Florence Rodale of the Rodale Institute. "Adults have already formed habits that are really hard to break," she says. "Children can be molded. If you place the right ideas in their minds, they will stick forever."

Starve a Cupboard

Beyond just eating better food, "You can choose to have a healthy, less-toxic, less-allergenic household," writes Lynn Marie Bower in Creating a Healthy Household, a thorough guide published by the Healthy House Institute. The Natural Resources Defense Council (NRDC) reports that 85 percent of U.S. households store at least one pesticide, and 47 percent of households with children under age five store at least one within their reach. Ridding cupboards of these chemicals is a good starting point. "All basic pest problems really come down to prevention," says Kagan Owens, program director of Beyond Pesticides. "Eliminate the things they"re attracted to," she suggests, such as moisture under sinks and food scraps around counters and floors.

Integrated pest management (IPM) uses less toxic measures to defeat serious invasions and can be extended to the front yard, where children typically roll and play. Of the 34 most commonly used lawn chemicals, 11 cause cancer; 20, nervous system poisoning; nine, birth defects; and 30, skin irritation. Safer alternatives exist, but parents can also take strategic steps like planting native grasses more likely to resist local pests.

Little arms thrown around a family pet can pose a serious health threat, as most pet products contain organophosphate pesticides, which are connected to both short-term hospitalizations and long-term ramifications such as increased risk of Parkinson"s disease. According to EPA research, a child can surpass the safe level of exposure by 500 times on the day of a flea treatment. The NRDC suggests combining simple physical measures, like regularly washing and brushing pets and mowing pet-frequented areas, with safer, non-pesticide products or new spot applications.

Returning from school with a headache and sore throat may signify an ordinary childhood bug, but it could also betray a much bigger problem. A 1999 U.S. General Accounting Office report confirms that 2,300 people were treated for pesticide poisonings that occurred at school between 1993 and 1996, although little information is available on either the amount or type of pesticides used in the nation"s 110,000 public schools. It"s no surprise then that most parents have no idea what their school"s pesticide policy is. Opening dialogue with school officials may lead to advance notification of pesticide use, or the restriction of the most potent pesticides in favor of less-toxic IPM techniques.

Don"t Stop There

"Though mean lead levels continue to decline, they remain a crushing reality for the highest-risk populations," says Don Ryan of the Alliance to End Childhood Lead Poisoning. Drinking water continues to carry lead from old plumbing, and 50 million housing units, including most homes built before 1960, still have lead paint on interior walls—a major source of exposure. And though lead was phased out of gasoline in the 1980s, it persists in soil, especially in urban areas with high traffic. The CDC recommends that all children living with such risk factors have their blood lead levels tested at 12 months and 24 months.

Emissions from cars, along with those from incinerators and power plants, constitute a particular health threat to urban children, who inhale more pollutants than adults. Jim Motavalli

"It"s a disgrace that one-third of preschool children in some neighborhoods are at risk," says Ryan. To limit the hazards, inspect your home for peeling paint, but don"t attempt to remove it yourself. Old paint is often better sealed off with a fresh coat. A simple home kit will measure lead levels in dust. You can also regularly wipe down surfaces and floors and clean children"s hands and toys. Lead continues to pervade some consumer products, such as mini-blinds, calcium supplements, antacids and hair dyes, so always check product labels.

Other steps to consider: Replace old thermometers with new, mercury-free varieties. Mercury released from broken thermometers may enter the water supply through drains or volatilize into indoor air. In 1998, more than 18,000 calls were made to poison control centers and emergency rooms because of them.

Even though the Consumer Product Safety Commission asked manufacturers two years ago to voluntarily eliminate phthalates (a chemical added to soften PVC, or vinyl plastic) from toys likely to be chewed by children, many products still contain high levels. Using cloth, wooden or non-PVC toys and teethers will help avoid direct exposure to these "probable human carcinogens," which are also linked to liver and kidney damage.

Have your tap water tested and filtered. American tap water has been found to contain microorganisms, arsenic, radon, lead and pesticides, and children consume two and a half times more water as a percentage of body weight than adults. The journal Epidemiology reported that an increased risk of birth defects is strongly associated with unfiltered and polluted tap water.

"About 85 percent of people with asthma also have allergies," says clinical allergist Dr. Jeff Wald. Controlling your home environment will help, he says. To stave off dust mites and animal dander, vacuum carpets and launder bedding and curtains frequently. To battle molds and mildews, ventilate rooms when showering and cooking, and use a dehumidifier on humid days. For severe asthma, watch for the local ground-level ozone warnings that are often reported in the news.

Secondha

nd tobacco smoke exposes children to some 4,000 substances, more than 40 of which are known cancer-causers in human beings or animals. In fact, environmental tobacco smoke is responsible for 150,000 to 300,000 lower respiratory infections a year (and 7,500 to 15,000 hospitalizations) in those younger than 18 months old. It aggravates asthma in as many as one million kids a year and has even been suspected to increase the risk of Sudden Infant Death Syndrome, which annually claims as many as 7,000 young lives.

Perchloroethylene (PCE), a solvent used in dry cleaning, is a neurotoxin also linked to liver and bladder cancer. It concentrates threefold in breast milk and can lead to jaundice in infants. Environmentally benign wet cleaning, on the other hand, does not cause fabric to off-gas chemicals or facilitate the release of PCE into groundwater.

When selecting wood for playgrounds and decks, avoid lumber that was pressure-treated with chromated copper arsenic (CCA). Unsafe levels of arsenic can leach out of the wood, onto children"s hands and into soil. Though it has been banned or restricted by nine other countries, many major retailers in the U.S. still sell it in playscapes and picnic tables.

Parents should not, however, try to place the entire toxic burden upon their own shoulders. "Not only is it overwhelming, but it"s not the right way to solve things in our society," says Daniel Swartz, executive director of the Children"s Environmental Health Network. "The government needs to take an active, strong role. We need to set safe standards."